Sansui AU-101 - weird boom / high-pitched sound / Feedback

Thanks guys.

I really appreciate your help and it's been of enormous help. Learnt a lot frankly. I have now played around with the set up / positioning and so far nothing of the sort and it's all been smooth.

Have been playing both turntable and other sources to test it out. Currently my speakers are around at a 2 feet distance from the turntable / at around same height. Using dedicated stands for the speakers but amp and turntable are still on an impromptu night stand - working really well though.

The room is quite small so I haven't cranked up the volume so much. I'll keep testing out and report back but so far it seems like it was the poor placement of turntable.

I think the speakers are still rather large for the room / small and wooden floorboards so I'll have to perhaps look into some sort of acoustic treatment (those acoustic foams etc.) but that's beyond my expertise currently and will require some further research! :)